Final answer:
Harmonic imaging is a technique that relies on the non-linear behavior of sound waves, using this effect to improve medical imaging quality by creating clearer images with less artifact.
Step-by-step explanation:
The option that relies on the non-linear behavior of the sound waves is Harmonic imaging. Harmonic imaging involves the use of the non-linear behavior of ultrasound waves as they pass through tissue. Non-linear behavior occurs when the tissue being imaged generates harmonics, which are frequencies of sound that are multiples of the original frequency. This is in contrast to the linear behavior where the response is directly proportional to the input, and there are no additional frequencies produced.
When an ultrasound wave with a certain frequency and amplitude travels through the body, tissues can cause distortion of the wave's waveform, resulting in the production of harmonic frequencies. These harmonics are useful in medical imaging because they can provide clearer images with less artifact than the fundamental frequency used in traditional ultrasound. This is particularly useful for improving the image quality of structures within the body.
On the other hand, CW Doppler relies on the Doppler shift, which is the change in frequency due to the relative motion of the source and observer. This technique is used to measure blood flow velocity, not the non-linear properties of sound waves.